update vector ics to handle megamorphic keyed loads

src/type-feedback-vector.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/ic/ic.h"
 #include "src/ic/ic-state.h"
 #include "src/objects.h"
 #include "src/type-feedback-vector-inl.h"
@@ skipping 246 matching lines @@
 }
 
 
 InlineCacheState KeyedLoadICNexus::StateFromFeedback() const {
   Isolate* isolate = GetIsolate();
   Object* feedback = GetFeedback();
   if (feedback == *vector()->UninitializedSentinel(isolate)) {
     return UNINITIALIZED;
   } else if (feedback == *vector()->PremonomorphicSentinel(isolate)) {
     return PREMONOMORPHIC;
-  } else if (feedback == *vector()->GenericSentinel(isolate)) {
-    return GENERIC;
+  } else if (feedback == *vector()->MegamorphicSentinel(isolate)) {
+    return MEGAMORPHIC;
   } else if (feedback->IsFixedArray()) {
     // Determine state purely by our structure, don't check if the maps are
     // cleared.
     FixedArray* array = FixedArray::cast(feedback);
     int length = array->length();
     DCHECK(length >= 3);
     return length == 3 ? MONOMORPHIC : POLYMORPHIC;
   }
 
   return UNINITIALIZED;
@@ skipping 37 matching lines @@
   SetFeedback(*vector()->UninitializedSentinel(GetIsolate()),
               SKIP_WRITE_BARRIER);
 }
 
 
 void CallICNexus::ConfigureMonomorphic(Handle<JSFunction> function) {
   SetFeedback(*function);
 }
 
 
-void KeyedLoadICNexus::ConfigureGeneric() {
-  SetFeedback(*vector()->GenericSentinel(GetIsolate()), SKIP_WRITE_BARRIER);
+void KeyedLoadICNexus::ConfigureMegamorphic() {
+  SetFeedback(*vector()->MegamorphicSentinel(GetIsolate()), SKIP_WRITE_BARRIER);
 }
 
 
 void LoadICNexus::ConfigureMegamorphic() {
   SetFeedback(*vector()->MegamorphicSentinel(GetIsolate()), SKIP_WRITE_BARRIER);
 }
 
 
 void LoadICNexus::ConfigurePremonomorphic() {
   SetFeedback(*vector()->PremonomorphicSentinel(GetIsolate()),
@@ skipping 169 matching lines @@
   if (feedback->IsFixedArray()) {
     FixedArray* array = FixedArray::cast(feedback);
     DCHECK(array->length() >= 3);
     Object* name = array->get(0);
     if (name->IsName()) return Name::cast(name);
   }
   return NULL;
 }
 }
 }  // namespace v8::internal